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Current Nifty Lot Size (65) & Bank Nifty (30) - Jan 2026

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Team Sahi

1 month ago3 min read

If you are trading in the Indian derivative markets today, the "old" rules no longer apply. As of January 1, 2026, the NSE has fully transitioned to the new lot size regime. Whether you are calculating your margin for a Nifty option trade or adjusting your hedge ratio for Bank Nifty, using the correct lot size is critical to avoiding order rejection or unintended over-exposure.

Below is the current, official lot size table for all major indices, including Nifty, Bank Nifty, and Sensex, effective for the January 2026 expiry and beyond.

Current Index Lot Sizes (Effective Jan 2026) 

Index Symbol Old Lot Size Current Lot Size (Jan 2026)
Nifty 50 NIFTY 75 65
Bank Nifty BANKNIFTY 35 30
Nifty Financial Services FINNIFTY 65 60
Nifty Mid Select MIDCPNIFTY 140 120
BSE Sensex SENSEX 10* 20

Note:

  • The Nifty Next 50 (NIFTYNXT50) contract continues with the same lot size of 25, with no change announced.
  • *SENSEX: While the NSE indices saw a reduction in lot sizes this January, the BSE Sensex remains at 20. The asterisk denotes that this lot size was increased from 10 earlier in 2025 following a regulatory review to align its contract value with its peers.

What Matters Right Now

As of 18 December, traders are in a transition phase:

  • All weekly and monthly contracts expiring up to December 30, 2025 will continue to trade with the existing lot sizes
  • Contracts expiring from January 2026 onward will reflect the revised lot sizes
  • All existing quarterly and half-yearly contracts, irrespective of their original introduction, will have their lot sizes revised after the December monthly expiry

In simple terms, December expiry is the dividing line between old and new lot structures.

Why Lot Sizes Keep Changing

Lot sizes are reviewed periodically to ensure that the notional value of derivative contracts remains manageable as index levels change over time.

This helps:

  • Keep contracts accessible for a wider set of traders
  • Improve risk containment
  • Prevent excessive capital concentration per lot
  • Maintain market efficiency and liquidity

The revised lots bring down exposure per contract, especially in Bank Nifty and Midcap Nifty, where absolute contract values had grown significantly.

What This Means for Traders Going Forward

1. Lower Exposure per Contract

With smaller lot sizes, each contract now represents slightly lower market exposure, which can be helpful for risk-controlled trading.

2. Changes in Position Sizing

If you trade fixed quantities (for example, 2–3 lots), your overall exposure and payoff profile will change from January onwards.

3. Option Selling & Hedging Adjustments

Option sellers should reassess:

  • Hedge ratios
  • Quantity-based risk limits
  • Margin deployment

Even a small lot size reduction can impact payoff symmetry and breakeven levels.

4. Spread Traders: Take Note

Certain day spread order books will not be available for specific contract combinations around the transition period, which is relevant for traders running calendar or spread strategies

What Traders Should Do Now

With the change now close at hand, traders should:

  • Review any open quarterly or long-dated positions
  • Clearly differentiate December expiry contracts vs January contracts
  • Check broker platforms for updated lot sizes and margin requirements
  • Avoid quantity mismatches while rolling over positions

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